Owing to wide application of the wireless communication technologies, use of various mobile apparatuses becomes increasingly widespread. Accordingly, the number of users becomes increasingly larger and requirements on wireless communication quality become ever heightened. This drives the wireless communication technologies to advance continuously. Among various wireless communication technologies, the most promising mobile wireless wideband technology is the Long Term Evolution (LTE) technology, which allows service providers to provide wireless wideband services in a more economical way and has performance superior to the existing 3rd-generation (3G) mobile communication technology.
In an LTE network, femtocells are deployed to extend coverage of wireless signals, to allow for network access in indoor environments and to improve the quality of service (QoS) in the indoor environments. However, in areas where femtocells are densely distributed, significant interference inevitably arises between the femtocells, which will seriously degrade the communication quality. Therefore, how to solve the problem of interference has become an important issue.
Generally speaking, an intuitive approach to avoid interference between the femtocells is to allocate different wireless resources to requests from different users so as to prevent occurrence of interference. Currently, all conventional technologies allocate wireless resources and revise use of the wireless resources through massive computations and frequent sensing operations performed by the femtocells. This has the following disadvantages: (1) the computational burden on the femtocells is very heavy; (2) additional cost (in terms of CPUs, memories and etc) is needed for the femtocells to make complex computations; (3) there is difficulty in resource allocation in areas where femtocells are densely distributed; (4) they fail to provide a mechanism of serving a large number of connections; (5) there lacks a design of guaranteeing the quality of service (QoS); (6) it is impossible to guarantee that the resources allocated are safe and immune to interference.
Accordingly, an urgent need exists in the art to provide a network system and a resource allocation method that can lower the cost of femtocells, allow for a high reusing rate of wireless frequency bands and dynamically allocate wireless resources in a flexible way.